An in-situ check can be made as follows:
1. Check for significant blue discolouration of the chain plates indicating excessive heat build-up.
2. Examine all pins for signs of rotation.
3. Check for cracking or deep scratching of the chain plates.
4. Check for severe wear of the inner plates as indicated in the diagram below.
For a more thorough check, proceed as follows:
1. Remove the chain from the engine.
2. Suspend the chain from a pin or hook with a 13 kg weight attached at the lower end.
3. Measure across 23 links as shown in the diagram. If the chain is within limits, the measurement should be no longer than 147.63 mm. Measurements beyond 147.63 mm indicate that the chain must be replaced.
Check for severe wear of the inner surface of the outer plates at the side-contact points with the sprocket teeth.
5. Check for signs of stiffness or kinking.
Check for severe wear of the plates in the area shown below.
If any of these symptoms are evident, the cam chain must be replaced.